Applications, Methods and Systems for a Laser Deliver Addressable Array

ABSTRACT

There is provided assemblies for combining a group of laser sources into a combined laser beam. There is further provided a blue diode laser array that combines the laser beams from an assembly of blue laser diodes. There are provided laser processing operations and applications using the combined blue laser beams from the laser diode arrays and modules.

This applications:

(i) claims under 35 U.S.C. § 119(e)(1) the benefit of U.S. provisionalapplication Ser. No. 62/193,047, filing date Jul. 15, 2015;

(ii) claims under 35 U.S.C. § 119(e)(1) the benefit of U.S. provisionalapplication Ser. No. 62/329,660, filing date Apr. 29, 2016;

(iii) claims under 35 U.S.C. § 119(e)(1) the benefit of U.S. provisionalapplication Ser. No. 62/329,786, filing date Apr. 29, 2016;

(iv) claims under 35 U.S.C. § 119(e)(1) the benefit of U.S. provisionalapplication Ser. No. 62/329,830, filing date Apr. 29, 2016;

(v) is a continuation-in-part of U.S. patent application Ser. No.14/787,393, filed Oct. 27, 2015, which is a US nationalization pursuantto 35 U.S.C. § 371 of PCT/US2014/035928 filed Apr. 29, 2014, and whichclaims priority to U.S. provisional patent application Ser. No.61/817,311, filed Apr. 29, 2013; and,

(vi) is a continuation-in-part of U.S. patent application Ser. No.14/837,782, filed Aug. 27, 2015, which claims under 35 U.S.C. §119(e)(1), the benefit of the filing date of U.S. provisionalapplication Ser. No. 62/042,785, filed Aug. 27, 2014, which claims under35 U.S.C. § 119(e)(1), the benefit of the filing date of U.S.provisional application Ser. No. 62/193,047, filed Jul. 15, 2015, and,which is a continuation-in-part of PCT application serialPCT/US14/035928, which claims under 35 U.S.C. § 119(e)(1), the benefitof the filing date of U.S. provisional application 61/817,311, filedApr. 29, 2013;

the entire disclosures of each of which is incorporated herein byreference.

BACKGROUND OF THE INVENTION Field of the Invention

The present inventions relate to array assemblies for combining laserbeams; and in particular array assemblies that can provide highbrightness laser beams for use in systems and applications inmanufacturing, fabricating, entertainment, graphics, imaging, analysis,monitoring, assembling, dental and medical fields.

Many lasers, and in particular semiconductor lasers, such as laserdiodes, provide laser beams having highly desirable wavelengths and beamquality, including brightness. These lasers can have wavelengths in thevisible range, UV range, IR range and combinations of these, as well as,higher and lower wavelengths. The art of semiconductor lasers, as wellas other laser sources, e.g., fiber lasers, is rapidly evolving with newlaser sources being continuously developed and providing existing andnew laser wavelengths. While having desirable beam qualities, many ofthese lasers have lower laser powers than are desirable, or needed forparticular applications. Thus, these lower powers have prevented theselaser sources from finding greater utility and commercial applications.

Additionally, prior efforts to combine these types of laser havegenerally been inadequate, for among other reasons, difficulty in beamalignment, difficulty in keeping the beams aligned during applications,loss of beam quality, difficulty in the special placement of the lasersources, size considerations, and power management, to name a few.

As used herein, unless expressly stated otherwise, the terms “blue laserbeams”, “blue lasers” and “blue” should be given their broadest meaning,and in general refer to systems that provide laser beams, laser beams,laser sources, e.g., lasers and diodes lasers, that provide, e.g.,propagate, a laser beam, or light having a wavelength from about 400 nmto about 500 nm.

Generally, the term “about” as used herein, unless specified otherwise,is meant to encompass a variance or range of ±10%, the experimental orinstrument error associated with obtaining the stated value, andpreferably the larger of these.

This Background of the Invention section is intended to introducevarious aspects of the art, which may be associated with embodiments ofthe present inventions. Thus the forgoing discussion in this sectionprovides a framework for better understanding the present inventions,and is not to be viewed as an admission of prior art.

SUMMARY

There has been a long-standing and unfulfilled need for, among otherthings, assemblies and systems to combine multiple laser beam sourcesinto a single or number of laser beams, while maintaining and enhancingdesired beam qualities, such as brightness and power. The presentinventions, among other things, solve these needs by providing thearticles of manufacture, devices and processes taught, and disclosedherein.

Thus, there is provided a laser system for performing laser operations,the system having: a plurality of laser diode assemblies; each laserdiode assembly having a plurality of laser diodes capable of producingan individual blue laser beam along a laser beam path; a means forspatially combining the individual blue laser beams to make a combinedlaser beam having a single spot in the far-field that is capable ofbeing coupled into a optical fiber for delivery to a target material;and, the means for spatially combining the individual blue laser beamson the laser beam path and in optical association with each laser diode.

Further there is provided the methods and systems having one or more ofthe following features: having at least three laser diode assemblies;and each laser diode assembly having at least 30 laser diodes; whereinthe laser diode assemblies are capable of propagating laser beams havinga total power of at least about 30 Watts, and a beam parameter propertyof less than 20 mm mrad; wherein the beam parameter property is lessthan 15 mm mrad; wherein the beam parameter property is less than 10 mmmrad; wherein the means for spatially combining produces a combinedlaser beam N times the brightness of the individual laser beam; whereinN is the number of laser diodes in the laser diode assembly; wherein themeans for spatially combining increases the power of the laser beamwhile preserving the brightness of the combined laser beam; whereby thecombined laser beam has a power that is at least 50× the power of theindividual laser beam and whereby a beam parameter product of thecombined laser beam is no greater than 2 times a beam parameter productof an individual laser beam; whereby the beam parameter product of thecombined laser beam is no greater than 0.1.5 times the beam parameterproduct of the individual laser beam; whereby the beam parameter productof the combined laser beam is no greater than 1 times the beam parameterproduct of the individual laser beam; wherein the means for spatiallycombining increases the power of the laser beam while preserving thebrightness of the individual laser beams; whereby the combined laserbeam has a power that is at least 100× the power of the individual laserbeam and whereby a beam parameter product of the combined laser beam isno greater than 2 times a beam parameter product of the individual laserbeam; whereby the beam parameter product of the combined laser beam isno greater than 1.5 times the beam parameter product of the individuallaser beam; whereby the beam parameter product of the combined laserbeam is no greater than 1 times of the beam parameter product of theindividual laser beam; wherein the optical fiber is solarizationresistant; wherein the means for spatially combining has assemblies,selected from the group consisting of alignment plane parallel platesand wedges, to correct for at least one of position errors or pointingerrors of a laser diode; wherein the means for spatially combining has apolarization beam combiner capable of increasing the effectivebrightness of the combined laser beams over the individual laser beams;wherein the laser diode assemblies define individual laser beam pathswith space between each of the paths, whereby the individual laser beamshave space between each beam; and wherein the means for spatiallycombining has a collimator for collimating the individual laser beams ina fast axis of the laser diodes, a periodic mirror for combining thecollimated laser beams, wherein the periodic mirror is configured toreflect a first laser beam from a first diode in the laser diodeassembly and transmits a second laser beam from a second diode in thelaser diode assembly, whereby the space between the individual laserbeams in the fast direction is filled; wherein the means for spatiallycombining has a patterned mirror on a glass substrate; wherein the glasssubstrate is of sufficient thickness to shift the vertical position of alaser beam from a laser diode to fill an empty space between the laserdiodes; and, having a stepped heat sink.

Still further there is provided a laser system for providing a highbrightness, high power laser beam, the system having: a plurality oflaser diode assemblies; each laser diode assembly having a plurality oflaser diodes capable of producing a blue laser beam having an initialbrightness; a means for spatially combining the blue laser beams to makea combined laser beam having a final brightness and forming a singlespot in the far-field that is capable of being coupled into a opticalfiber; wherein each laser diode is locked by an external cavity to adifferent wavelength to substantially increase the brightness of thecombined laser beam, whereby the final brightness of the combined laserbeam is about the same as the initial brightness of the laser beams fromthe laser diode.

Further there is provided the methods and systems having one or more ofthe following features: wherein each laser diode is locked to a singlewavelength using an external cavity based on a grating and each of thelaser diode assembly are combined into a combined beam using a combiningmeans selected from the group consisting of a narrowly spaced opticalfilter and a grating; wherein the Raman convertor is an optical fiberthat has a pure fused silica core to create a higher brightness sourceand a fluorinated outer core to contain the blue pump light; wherein theRaman convertor is used to pump a Raman convertor such as an opticalfiber that has a GeO₂ doped central core with an outer core to create ahigher brightness source and an outer core that is larger than thecentral core to contain the blue pump light; wherein the Raman convertoris an optical fiber that has a P₂O₅ doped core to create a higherbrightness source and an outer core that is larger than the central coreto contain the blue pump light; wherein the Raman convertor an opticalfiber that has a graded index core to create a higher brightness sourceand an outer core that is larger than the central core to contain theblue pump light; wherein the Raman convertor is a graded index GeO₂doped core and an outer step index core; wherein the Raman convertor isused to pump a Raman convertor fiber that is a graded index P₂O₅ dopedcore and an outer step index core; wherein the Raman convertor is usedto pump a Raman convertor fiber that is a graded index GeO₂ doped core;wherein the Raman convertor is a graded index P₂O₅ doped core and anouter step index core; wherein the Raman convertor is a diamond tocreate a higher brightness laser source; wherein the Raman convertor isa KGW to create a higher brightness laser source; wherein the Ramanconvertor is a YVO₄ to create a higher brightness laser source; whereinthe Raman convertor is a Ba(NO₃)₂ to create a higher brightness lasersource; and, wherein the Raman convertor is a high pressure gas tocreate a higher brightness laser source.

Still further there is provided a laser system for performing laseroperations, the system having: a plurality of laser diode assemblies;each laser diode assembly having a plurality of laser diodes capable ofproducing a blue laser beam along a laser beam path; a means forspatially combining the blue laser beams to make a combined laser beamhaving a single spot in the far-field that is capable of being opticallycoupled to a Raman convertor, to pump the Raman converter, to increasethe brightness of the combined laser beam.

Additionally there is provided a method of providing a combined laserbeam, the method having operation an array of Raman converted lasers togenerate blue laser beams at individual different wavelengths andcombined the laser beams to create a higher power source whilepreserving the spatial brightness of the original source.

Yet further there is provided a laser system for performing laseroperations, the system having: a plurality of laser diode assemblies;each laser diode assembly having a plurality of laser diodes capable ofproducing a blue laser beam along a laser beam path; beam collimatingand combining optics along the laser beam path, wherein a combined laserbeam is capable of being provided; and an optical fiber for receivingthe combined laser beam.

Moreover there is provided the methods and systems having one or more ofthe following features: wherein the optical fiber is in opticalcommunication with a rare-earth doped fiber, whereby the combined laserbeam is capable of pumping the rare-earth doped fiber to create a higherbrightness laser source; and, wherein the optical fiber is in opticalcommunication with an outer core of a brightness convertor, whereby thecombined laser beam is capable of pumping the outer core of a brightnessconvertor to create a higher ratio of brightness enhancement.

Still further the is provided a Raman fiber having: dual cores, whereinone of the dual cores is a high brightness central core; and, a means tosuppress a second order Raman signal in the high brightness central coreselected from the group consisting of a filter, a fiber bragg grating, adifference in V number for the first order and second order Ramansignals, and a difference in micro-bend losses.

In addition there is provided a second harmonic generation system, thesystem having: a Raman convertor at a first wavelength to generate lightat half the wavelength of the first wavelength; and an externallyresonant doubling crystal configured to prevent the half wavelengthlight from propagating through the optical fiber.

Moreover there is provided the methods and systems having one or more ofthe following features: wherein the first wave length is about 460 nm;and the externally resonant doubling crystal is KTP; and, wherein theRaman convertor has a non-circular outer core structured to improveRaman conversion efficiency.

Further there is provided a third harmonic generation system, the systemhaving: a Raman convertor at a first wavelength to generate light at asecond lower wavelength than the first wavelength; and an externallyresonant doubling crystal configured to prevent the lower wavelengthlight from propagating through the optical fiber.

Further there is provided a fourth harmonic generation system, thesystem having: a Raman convertor to generate light at 57.5 nm using anexternally resonant doubling crystal configured to prevent the 57.5 nmwavelength light from propagating through the optical fiber.

Further there is provided a second harmonic generation system, thesystem having a rare-earth doped brightness convertor having Thuliumthat lases at 473 nm when pumped by an array of blue laser diodes at 450nm, to generate light at half the wavelength of the source laser or236.5 nm using an externally resonant doubling crystal but does notallow the short wavelength light to propagate through the optical fiber.

Further there is provided a third harmonic generation system, the systemhaving a rare-earth doped brightness convertor, having Thulium thatlases at 473 nm when pumped by an array of blue laser diodes at 450 nmto generate light at 118.25 nm using an externally resonant doublingcrystal but does not allow the short wavelength light to propagatethrough the optical fiber.

Further there is provided a fourth harmonic generation system, thesystem having a rare-earth doped brightness convertor, having Thuliumthat lases at 473 nm when pumped by an array of blue laser diodes at 450nm to generate light at 59.1 nm using an externally resonant doublingcrystal but does not allow the short wavelength light to propagatethrough the optical fiber.

Still additionally there is provided a laser system for performing laseroperations, the system having: at least three of laser diode assemblies;each of the at least laser diode assemblies has at least ten laserdiodes, wherein each of the at least ten laser diodes is capable ofproducing a blue laser beam, having a power of at least about 2 Wattsand a beam parameter product of less than 8 mm-mrad, along a laser beampath, wherein each laser beam path is essentially parallel, whereby aspace is defined between the laser beams traveling along the laser beampaths; a means for spatially combining and preserving brightness of theblue laser beams positioned on all of the at least thirty laser beampaths, the means for spatially combining and preserving brightnesshaving a collimating optic for a first axis of a laser beam, a verticalprism array for a second axis of the laser beam, and a telescope;whereby the means for spatially combining and preserving fills in thespace between the laser beams with laser energy, thereby providing acombined laser beam a power of at least about 600 Watts, and a beamparameter product of less than 40 mm-mrad.

Yet further there is provided an addressable array laser processingsystem, the addressable array laser processing system having: at leastthree laser systems of the type presently described; each of the atleast three laser systems configured to couple each of their combinedlaser beams into a single optical fiber; whereby each of the at leastthe three combined laser beams being capable of being transmitted alongits coupled optical fiber; the at least three optical fibers in opticalassociation with a laser head; and a control system; wherein the controlsystem has a program having a predetermined sequence for delivering eachof the combined laser beams at a predetermined position on a targetmaterial.

Moreover there is provided the methods and systems for an addressablearray having one or more of the following features: wherein apredetermined sequence for delivering having individually turning on andoff the laser beams from the laser head, thereby imaging onto a bed ofpowder to melt and fuse the target material having a powder into a part;wherein the fibers in the laser head are configured in an arrangementselected from the group consisting of linear, non-linear, circular,rhomboid, square, triangular, and hexagonal; wherein the fibers in thelaser head are configured in an arrangement selected from the groupconsisting of 2×5, 5×2, 4×5, at least 5× at least 5, 10×5, 5×10 and 3×4;wherein the target material has a powder bed; and, having: an x-y motionsystem, capable of transporting the laser head across a powder bed,thereby melting and fusing the powder bed; and a powder delivery systempositioned behind the laser source to provide a fresh powder layerbehind the fused layer; having: a z-motion system, capable oftransporting the laser head to increment and decrement a height of thelaser head above a surface of the powder bed; having: a bi-directionalpowder placement device capable of placing powder directly behind thedelivered laser beam as it travels in the positive x direction or thenegative x direction; having a powder feed system that is coaxial with aplurality of laser beam paths; having a gravity feed powder system;having a powder feed system, wherein the powder is entrained in an inertgas flow; having a powder feed system that is transverse to N laserbeams where N≥1 and the powder is placed by gravity ahead of the laserbeams; and having a powder feed system that is transverse to N laserbeams where N≥1 and the powder is entrained in an inert gas flow whichintersects the laser beams.

Yet still further there is provided a method of providing a combinedblue laser beam having high brightness, the method having: operating aplurality of Raman converted lasers to provide a plurality of individualblue laser beams and combining the individual blue laser beams to createa higher power source while preserving the spatial brightness of theoriginal source; wherein the individual laser beams of the pluralityhave different wavelengths.

Moreover there is provided a method of laser processing a targetmaterial, the method having: operating an addressable array laserprocessing system having at least three laser systems of the type of thepresently described systems to generate three individual combined laserbeams into three individual optical fibers; transmitting each combinedlaser beams along its optical fiber to a laser head; and directing thethree individual combined laser beams from the laser head in apredetermined sequence at a predetermined position on a target material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing laser performance of embodiments in accordancewith the present inventions.

FIG. 2A is a schematic of a laser diode and axis focusing lens inaccordance with the present inventions.

FIG. 2B is a schematic of an embodiment of a laser diode spot after fastand slow axis focusing in accordance with the present inventions.

FIG. 2C is a prospective view of an embodiment of a laser diode assemblyin accordance with the present inventions.

FIG. 2D is a prospective view of an embodiment of a laser diode modulein accordance with the present inventions.

FIG. 2E is a partial view of the embodiment of FIG. 2C showing laserbeams, laser beam paths and space between the laser beams in accordancewith the present inventions.

FIG. 2F is a cross sectional view of the laser beams, laser beam pathsand space between the laser beams of FIG. 2E.

FIG. 2G is a prospective view of an embodiment of laser beams, beampaths and optics in accordance with the present inventions.

FIG. 2H is a view of the combined laser diode beams after the patternedmirrors in accordance with the present invention.

FIG. 2I is a view of the laser diode beams after the beam folder with aneven split of the beams in accordance with the present invention.

FIG. 2J is a view of a laser diode beams after the beam folder with a3-2 column split in accordance with the present invention.

FIG. 3 is a schematic illustrating an embodiment of scanning of anembodiment of a laser diode array on a starting or target material inaccordance with the present inventions.

FIG. 4 is a table providing processing parameters in accordance with thepresent inventions.

FIG. 5 is a schematic of an embodiment of a laser array system andprocess in accordance with the present inventions.

FIG. 6 is a schematic of an embodiment of a laser array system andprocess in accordance with the present inventions.

FIG. 7 is a schematic of an embodiment of a laser array system andprocess in accordance with the present inventions.

FIG. 8 is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 9 is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 10 is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 11 is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 12 is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 13 is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 14A is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 14B is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 14C is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 15A is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 15B is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 16A is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 16B is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 16C is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

FIG. 16D is a schematic of an embodiment of a laser fiber bundlearrangement for use in an embodiment of a laser array system inaccordance with the present inventions.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In general, the present inventions relate to the combining of laserbeams, systems for making these combinations and processes utilizing thecombined beams. In particular, the present inventions relate to arrays,assemblies and devices for combining laser beams from several laser beamsources into one or more combined laser beams. These combined laserbeams preferably have preserved, enhanced, and both, various aspects andproperties of the laser beams from the individual sources.

Embodiments of the present array assemblies, and the combined laserbeams that they provide can find wide-ranging applicability. Embodimentsof the present array assemblies are compact and durable. The presentarray assemblies have applicability in: welding, additive manufacturing,including 3-D printing; additive manufacturing-milling systems, e.g.,additive and subtractive manufacturing; astronomy; meteorology; imaging;projection, including entertainment; and medicine, including dental, toname a few.

Although this specification focuses on blue laser diode arrays, itshould be understood that this embodiment is only illustrative of thetypes of array assemblies, systems, processes and combined laser beamscontemplated by the present inventions. Thus, embodiments of the presentinventions include array assemblies for combining laser beam fromvarious laser beam sources, such as solid state lasers, fiber lasers,semiconductor lasers, as well as other types of lasers and combinationsand variations of these. Embodiments of the present invention includethe combining of laser beams across all wavelengths, for example laserbeams having wavelengths from about 380 nm to 800 nm (e.g., visiblelight), from about 400 nm to about 880 nm, from about 100 nm to about400 nm, from 700 nm to 1 mm, and combinations, variations of particularwavelengths within these various ranges. Embodiments of the presentarrays may also find application in microwave coherent radiation (e.g.,wavelength greater than about 1 mm). Embodiments of the present arrayscan combine beams from one, two, three, tens, or hundreds of lasersources. These laser beams can have from a few mil watts, to watts, tokilowatts.

An embodiment of the present invention consists of an array of bluelaser diodes that are combined in a configuration to preferably create ahigh brightness laser source. This high brightness laser source may beused directly to process materials, i.e. marking, cutting, welding,brazing, heat treating, annealing. The materials to be processed, e.g.,starting materials or target materials, can include any material orcomponent or composition, and for example, can include semiconductorcomponents such as but not limited to TFTs (thin film transistors), 3-Dprinting starting materials, metals including gold, silver, platinum,aluminum and copper, plastics, tissue, and semiconductor wafers to namea few. The direct processing may include, for example, the ablation ofgold from electronics, projection displays, and laser light shows, toname a few.

Embodiments of the present high brightness laser sources may also beused to pump a Raman laser or an Anti-Stokes laser. The Raman medium maybe a fiber optic, or a crystal such as diamond, KGW (potassiumgadolinium tungstate, KGd(WO₄)₂), YVO₄, and Ba(NO₃)₂. In an embodimentthe high brightness laser sources are blue laser diode sources, whichare a semiconductor device operating in the wavelength range of 400 nmto 500 nm. The Raman medium is a brightness convertor and is capable ofincreasing the brightness of the blue laser diode sources. Thebrightness enhancement may extend all the way to creating a single mode,diffraction limited source, i.e., beam having an M² of about 1 and 1.5with beam parameter products of less than 1, less than 0.7, less than0.5, less than 0.2 and less than 0.13 mm-mrad depending upon wavelength.

In an embodiment “n” or “N” (e.g., two, three, four, etc., tens,hundreds, or more) laser diode sources can be configured in a bundle ofoptical fibers that enables an addressable light source that can be usedto mark, melt, weld, ablate, anneal, heat treat, cut materials, andcombinations and variations of these, to name a few laser operations andprocedures.

An array of blue laser diodes can be combined, with an optical assembly,to create a high brightness direct diode laser system, which can providea high brightness combined laser beam. FIG. 1 shows a table 100 for thelaser performance (beam parameter product vs. laser power in W (Watts))of embodiments of a range of beam parameter products when using a fibercombiner technique with the brightness ranging from 8 mm-mrad at 200Watts to 45 mm-mrad at 4000 Watts. Line 101 plots the performance for anembodiment of a laser diode array. Line 102 plots the performance ofdense wavelength beam combined arrays. Line 103 plots the performance ofthe brightness converting technology when scaled using a fiber combinertechnique. Line 104 plots the performance of the brightness convertingtechnology when using dense wavelength combining of the outputs of thebrightness convertor. This allows the combined beam to remain a singlespatial mode or a near single spatial mode as the power level is scaled.The dense wavelength combining uses gratings to control the wavelengthof each individual brightness converted laser, followed by gratings tocombing the beams into a single beam. The gratings can be ruledgratings, holographic gratings, Fiber Bragg Gratings (FBG), or VolumeBragg Gratings (VBG). It is also feasible to use a prism, although thepreferred embodiment is to use the gratings.

FIG. 2A is a schematic of a laser diode 200 that is propagating a laserbeam along a laser beam path to a Fast Axis Collimating lens 201 (FAC).A 1.1, 1.2, 1.5, 2 or even 4 mm, cylindrical aspheric lens is used tocapture the fast axis power and create a diffraction limited beam in thefast axis with the correct height to preserve the brightness and allow acombination of the beams further down the optical chain. The collimatinglens 202 is for collimating the slow axis of the laser diode (the axiswith the smaller divergence angle, typically the x axis). A 15, 16, 17,18 or 21 mm focal length cylindrical aspheric lens captures the slowaxis power and collimates the slow axis to preserve the brightness ofthe laser source. The focal length of the slow axis collimator resultsin an optimized combination of the laser beam lets by the optical systeminto the target fiber diameter. In preferred embodiments of the arrays,both a slow axis and a fast axis collimating lens are located along eachof the laser beam paths and are used to shape the individual laserbeams.

FIG. 2B is a schematic of a laser beam spot 203 that was formed by thelaser beam from a laser diode passing through both a fast and slow axisfocusing lens. This simulation takes into account the maximum divergenceof the source across the complete aperture of the source. It beingunderstood that many different shaped laser beam spots can be created,such as a square, rectangle, circle, oval, linear and combinations andvariations of these and other shapes. For example, the combined laserbeam creates a spot 203, with blue laser light, focused to a spot sizeof 100 μm with 100 mm focal length lens, at an NA of 0.18.

Turning to FIGS. 2C and 2D there is shown an embodiment of a laser diodesubassembly 210 (e.g., diode module, bar, plate, multi-die package) anda laser diode module 220 having four laser diode assemblies 210, 210 a,210 b, 210 c.

In FIG. 2E there is shown a detailed view showing portions of some ofthe laser beams 250 a, 251 a, 252 a, along their respective laser beampaths 250, 251, 252. FIG. 2F is a cross sectional view of the laserbeams of FIG. 2E, showing the open space horizontal 260 and vertical 261(based upon the orientation of the figure). The beam combining opticscloses the beams spatially together, to eliminate the open spaces, e.g.,260, 261, in the final spot 203 (FIG. 2B).

The laser diode module 220 is capable of producing a combined laserbeam, preferably a combined blue laser beam, having the performance ofthe curve 101 of FIG. 1. The laser diode assembly 210 has a baseplate211, which is a thermally conductive material, e.g., copper, that haspower leads (e.g., wires) e.g., 212, entering to provide electricalpower to the diodes, e.g., 213. In this embodiment of the multi-diepackage, there are 20 laser diodes, e.g., 213, arranged in a 5×4configuration behind a cover plate. Other configurations arecontemplated, e.g., 4×4, 4×6, 5×6 10×20, 30×5, and in development today,etc., and combinations and variations of these, to provide n×n diodes inan assembly. Each diode may have a plane parallel plate for translatingthe position of the beam in the slow axis, e.g., 214 when using a singleslow axis collimating (SAC) lens across multiple rows, e.g., 216. Theplane parallel plate is not necessary when using individual slow axislenses for each laser diode, which is the preferred embodiment. Theplane parallel plates correct the position of the laser beam path in theslow axis as it propagates from each of the individual laser diodes,which may be a result of the assembly process. The plane parallel platesare not required if individual FAC/SAC lens pairs are used for eachlaser diode. The SAC position compensates for any assembly errors in thepackage. The result of both of these approaches is to align the beamletsto be parallel when either using individual lens pairs (FAC/SAC) or ashared SAC lens after individual FAC/plane parallel plates, providingparallel and spaced laser beams, e.g., 251 a, 252 a, 250 a, and beampaths, e.g., 251, 252, 250.

The composite beam from each of the laser diode subassemblies, 210, 210a, 210 b, 210 c, propagate to a patterned mirror, e.g., 225, which isused to redirect and combine the beams from the four laser diodesubassemblies into a single beam, as shown in FIG. 2G. The four rows ofcollimate laser diodes are interlaced with the four rows of the otherthree packages creating the composite beam. FIG. 2H shows the positionof the beams, e.g., 230, from laser subassembly 210. An aperture stop235 clips off any unwanted scattered light from the combined beam lets,which reduces the heat load on the fiber input face. A polarization beamfolding assembly 227 folds the beam in half in the slow axis to doublethe brightness of the composite laser diode beam FIG. 2I. The beam canbe folded either by splitting the central emitter in the centerresulting the pattern shown in FIG. 2I, where beam 231 is the overlay oftwo beam lets in the slow axis direction by polarization, and beam 232is the split beam let which does not overlay any other emitters. If thebeam is split in between the 2^(nd) and 3^(rd) beamlet (FIG. 2J), thenthe beam folder is more efficient and two of the columns of beams, e.g.,233 are overlapped, while the third column of beams, e.g, 234 simplypasses straight through. The telescope assembly 228 either expands thecombined laser beams in the slow axis or compresses the fast axis toenable the use of a smaller lens. The telescope 228 shown in thisexample (FIG. 2G) expands the beam by a factor of 2.6×, increasing itssize from 11 mm to 28.6 mm while reducing the divergence of the slowaxis by the same factor of 2.6×. If the telescope assembly compressesthe fast axis then it would be a 2× telescope to reduce the fast axisfrom 22 mm height (total composite beam) to 11 mm height giving acomposite beam that is 11 mm×11 mm. This is the preferred embodiment,because of the lower cost. An aspheric lens 229 focuses the compositebeam into an optical fiber 245 that is at least 50, 100, 150, or 200 μmin diameter. The fiber output of multiple laser diode modules 220 arecombined with a fiber combiner to produce higher output power levellasers according to FIG. 1 (line 101). The laser diode modules arecombined using an optical combination method where the aspheric lens 229and fiber combiner 240 are replaced with a set of shearing mirrors thatthen couple into an aspheric lens and the composite beam launched intothe end of an optical fiber. In this manner one, two, three, tens, andhundreds of laser diode modules can be optically associated and theirlaser beams combined. In this manner combined laser beams can themselvesbe further, or additionally, combined to form a multiple-combined laserbeam.

In the embodiment of FIGS. 2C and 2D, the configuration makes itfeasible to launch, for example, up to 200 Watts of laser beam powerinto a single 50, 100, 150, or 200 μm core optical fiber. Thisembodiment of FIGS. 2C and 2D shows typical components to make, forexample, a 200 W diode array assembly, e.g. a 200 W combined module,which uses up to four 50 Watt individual diode assemblies, e.g., 50 Wattmodules.

It being understood that configurations, powers and combined beamnumbers are feasible. The embodiment of FIGS. 2C and 2D minimizes theelectrical connections from the power supply to the laser diodes.

Thus, the individual modules, the combined modules, and both can beconfigured to provide a single combined laser beam or multiple combinedlaser beams, e.g., two, three, four, tens, hundreds or more. These laserbeams can each be launched in a single fiber, or they can be furthercombined to be launched into fewer fibers. Thus, by way of illustration12 combined laser beams can be launched into 12 fibers, or the 12 beamscan be combined and launched into fewer than 12 fibers, e.g., 10, 8, 6,4 or 3 fibers. It should be understood that this combining can be ofdifferent power beams, to either balance or unbalance the powerdistribution between individual fibers; and can be of beams havingdifferent or the same wavelengths.

In an embodiment the brightness of an array of laser diodes can beimproved by operating each array at a different wavelength and thencombining them with either a grating or series of narrow band dichroicfilters. The brightness scaling of this technology is shown in FIG. 1 asthe near straight line 102. The starting point is the same brightness ascan be achieved by a single module, since each module will be spatiallyoverlapped on the previous modules in a linear fashion, the fiberdiameter does not change, but the power launched does result in a higherbrightness from the wavelength beam combined modules.

In an embodiment an array of blue laser diodes can be converted to nearsingle mode or single mode output with the help of a brightnessconvertor. The brightness convertor can be an optical fiber, a crystalor a gas. The conversion process proceeds via Stimulated RamanScattering which is achieved by launching the output from an array ofblue laser diodes into an optical fiber or crystal or gas with aresonator cavity. The blue laser diode power is converted via StimulatedRaman Scattering to gain and the laser resonator oscillates on the firstStokes Raman line, which is offset from the pump wavelength by theStokes shift. For example the embodiment shown in FIG. 3 and associateddisclosure in the specification of U.S. patent application Ser. No.14/787,393, which is based upon WO 2014/179345, the entire disclosure ofwhich is incorporated herein by reference. The performancecharacteristics of this technology is shown in FIG. 1, line 103 with thebrightness beginning at 0.3 mm-mrad for a 200 W laser and 2 mm-mrad fora 4000 W laser when using a fiber combiner to combine multiple highbrightness laser beams.

The brightness of a blue laser source can be further increased bycombining the outputs of the brightness converted sources. Theperformance of this type of embodiment is shown by line 104 of FIG. 1.Here the brightness is defined by the starting module at 0.3 mm-mrad.The gain-bandwidth of the Raman line is substantially broader than thatof the laser diodes, so more lasers can be combined via wavelength thanfor the laser diode technology alone. The result is a 4 kW laser with abrightness the same as the 200 W laser, or 0.3 mm-mrad. This isindicated on FIG. 1 by the flat line 104.

The technology of the present inventions described in this specificationcan be used to configure a laser system for a wide range of applicationsranging from welding, cutting, brazing, heat treating, sculpting,shaping, forming, joining, annealing and ablating, and combinations ofthese and various other material processing operations. While thepreferred laser sources are relatively high brightness, the presentinventions provide for the ability to configure systems to meet lowerbrightness requirements. Furthermore, groups of these lasers can becombined into a long line, which can be used to perform laser operationson larger areas of target materials, such as for example, annealinglarge area semiconductor devices such as the TFT's of a flat paneldisplay.

The output of either the laser diodes, laser diode arrays, wavelengthcombined laser diode arrays, brightness converted laser diode arrays andwavelength combined laser diode arrays can be used to create a uniqueindividually addressable printing machine. Since the laser power fromeach module is sufficient to melt and fuse plastic, as well as, metalpowders, these sources are ideal for the additive manufacturingapplication, as well as additive-subtractive manufacturing applications(i.e., the present laser additive manufacturing system is combined withtraditional removing manufacturing technologies, such as CNC machines,or other types of milling machines, as well as laser removal orablation). Because of their, capability to provide small spot sizes,precision, and other factors, the present systems and laserconfigurations may also find applications in micro and nano additive,subtractive and additive-subtractive manufacturing technologies. Anarray of lasers that are individually connected, can be imaged onto thepowder surface to create an object at n times the speed of a singlescanned laser source. The speed can be further increased by using ahigher power laser for each of the n-spots. When using the brightnessconverted lasers, a near diffraction limited spot can be achieved foreach of the n-spots, thus making it feasible to create higher resolutionparts because of the sub-micron nature of the individual spot formedwith a blue high brightness laser source. This smaller spot size of thepresent configurations and systems provides a substantial improvement inthe processing speed and the resolution of the printing process,compared to prior art 3-D printing technology. When combined with aportable powder feed device, embodiments of the present systems cancontinuously print layer after layer at a speeds in excess of 100× theprint speeds of prior art additive manufacturing machines. By enablingthe system to deposit powder as the positioning devices moves either ina positive or negative direction just behind the laser fusing spots(e.g., FIG. 5, powder device 508, powder device 508 b), the system cancontinuously print without having to stop to apply or level the powderrequired for the next layer.

Turning to FIG. 3 there is a schematic of a laser process with a lasersystem having two rows of staggered spots, e.g., 303 a and spots, e.g.,303 b. The laser spots, e.g., 303 a, 303 b are moved, e.g., scanned, inthe direction of arrow 301 across the target material. The targetmaterial could be in a power form 302, which is then melted buy thelaser spots 304 and then solidifies, generally along transition line305, to form as a fused material 306. The powers of the beam, the firingtime of the beams, the speed of movement and the combinations of these,can be varied in a predetermined manner resulting in a predeterminedshape of the melt transition line 305. The distance the beam can bestaggered can be 0, 0.1, 0.5, 1, 2 mm apart as needed by the fixturingrequired to hold the fibers and their optical components. The staggermay also be a monotonically increasing or decreasing position at a setstagger step-size or a varying step-size. The exact speed advantage willdepend on the target material and configuration of the parts to bemanufactured.

FIG. 4 summarizes the performance than can achieved for embodiments ofthe laser systems and configurations, such as those depicted in FIGS.5-7 for a 20 beam system, the speed increases with each additional beamthat is added to the system.

Turning to FIG. 5 there is provided a schematic of an embodiment of alaser system with an addressable laser delivery configuration. Thesystem has an addressable laser diode system 501. The system 501provides independently addressable laser beams to a plurality of fibers502 a, 502 b, 502 c (greater and lower numbers of fibers and laser beamsare contemplated). The fibers 502 a, 502 b, 502 c are combined into afiber bundle 504 that is contained in protective tube 503, or cover. Thefibers 502 a, 502 b, 502 c in fiber bundle 504 are fused together toform a printing head 505 that includes an optics assembly 506 thatfocuses and directs the laser beams, along beam paths, to a targetmaterial 507. The print head and the powder hoppers move together withthe movement of the print head being in the positive direction accordingto 510. Additional material 509 can be placed on top of the fusedmaterial 507 with each pass of the print head or hopper. The print headis bi-directional and will fuse material in both directions as the printhead moves, so the powder hoppers operate behind the print headproviding the buildup material to be fused on the next pass of the laserprinting head.

By “addressable array” it is meant that one or more of: the power;duration of firing; sequence of firing; position of firing; the power ofthe beam; the shape of the beam spot, as well as, the focal length,e.g., depth of penetration in the z-direction, can be independentlyvaried, controlled and predetermined or each laser beam in each fiber toprovide precise and predetermined delivery patterns that can create fromthe target material highly precise end products (e.g., built materials)Embodiments of addressable arrays can also have the ability forindividual beams and laser stops created by those beam to performvaried, predetermined and precise laser operations such as annealing,ablating, and melting.

Turning to FIG. 6 there is provided a schematic of an embodiment of alaser system with an addressable laser delivery configuration. The lasersystem can be a laser diode array system, a brightness converted systemor a high power fiber laser system. The system has an addressable lasersystem 601. The system 601 provides independently addressable laserbeams to a plurality of fibers 602 a, 602 b, 602 c (greater and lowernumbers of fibers and laser beams are contemplated). The fibers 602 a,602 b, 602 c are combined into a fiber bundle 604 that is contained inprotective tube 603, or cover. The fibers 602 a, 602 b, 602 c in fiberbundle 604 are fused together to form a printing head 605 that includesan optics assembly 606 that focuses and directs the laser beams, alongbeam paths, to a target material 607. The target material 607 can beannealed, to form an annealed material 609. The direction of movement ofthe laser head is shown by arrow 610.

Turning to FIG. 7 there is provided a schematic of an embodiment of alaser system with an addressable laser delivery configuration. Thesystem has an addressable laser diode system 701. The system 701provides independently addressable laser beams to a plurality of fibers702 a, 702 b, 702 c (greater and lower numbers of fibers and laser beamsare contemplated). The fibers 702 a, 702 b, 702 c are combined into afiber bundle 704 that is contained in protective tube 703, or cover. Thefibers 702 a, 702 b, 702 c in fiber bundle 704 are fused together toform a printing head powder distribution head 720. The powderdistribution head 720 can have the powder delivered coaxially with thelaser beams, or transverse with the laser beams. The powder distributionhead 720 provides a layer of additional material 709, which is fused toand on the top of the target material 707. The direction of movement ofthe laser head is shown by arrow 710.

FIG. 8 shows a configuration of a bundle 800 of fibers, e.g., 801, thatare fused together, and are used in the laser head of a system such asthe systems shown in FIGS. 5-7. The configuration will deliver laserspots configured similarly to the fiber arrangement. In this embodiment,there are five fibers in a single linear row, a 1×5 linearconfiguration. A 1×n linear row of fibers is the ultimate laser printinghead, where n is dependent on the physical extent of the product to beprinted.

FIG. 9 shows a configuration of a bundle 900 of fibers, e.g., 901, thatare fused together, and are used in the laser head of a system such asthe systems shown in FIGS. 5-8. The configuration has two linear rows902, 903 of fibers that are staggered and arranged in a rhomboidarrangement. The fibers will deliver laser spots configured similarly tothe fiber arrangement. In this embodiment there are two rows of fivefibers in each linear row, a 2×5 linear configuration.

FIG. 10 shows a configuration of a bundle (1000) of fibers, e.g., 1001,that are fused together, and are used in a head of a system such as thesystems shown in FIGS. 5-8. The configuration has three linear rows1002, 1003, 1004 of fibers that are staggered and arranged in a rhomboidarrangement. The fibers will deliver laser spots configured similarly tothe fiber arrangement. In this embodiment, there are three rows of fivefibers in each linear row, a 3×5 linear configuration.

FIG. 11 shows a configuration of a bundle 1100 of fibers, e.g., 1101,that are fused together, and are used in a head of a system such as thesystems shown in FIGS. 5-8. The configuration has three linear rows1102, 1103, 1104 of fibers that are staggered and arranged in triangulararrangement. The fibers will deliver laser spots configured similarly tothe fiber arrangement. In this embodiment, there are three rows of fivefibers in each linear row, a 3×5 linear configuration.

FIG. 12 shows a configuration of a bundle 1200 of fibers, e.g., 1201,that are fused together, and are used in a head of a system such as thesystems shown in FIGS. 5-8. The configuration has four linear rows 1202,1203, 1204, 1205 of fibers that are not staggered and arranged in asquare arrangement. The fibers will deliver laser spots configuredsimilarly to the fiber arrangement. In this embodiment, there are fourrows of four fibers in each linear row, a 4×4 linear configuration.

FIG. 13 shows a configuration of a bundle 1300 of fibers, e.g., 1301,that are fused together, and are used in a head of a system such as thesystems shown in FIGS. 5-8. The configuration has five linear rows,e.g., 1302. The fibers are not staggered and are arranged in a squarearrangement. The fibers will deliver laser spots configured similarly tothe fiber arrangement. In this embodiment, there are five rows of fourfibers in each linear row, a 5×4 linear configuration.

FIG. 14A shows a configuration of a bundle 1401 of five (n=5) fibers,e.g., 1401 a arranged in a circular configuration.

FIG. 14B shows a configuration of a bundle 1402 of nine (n=9) fibers,e.g., 1402 a arranged in a circular configuration having a fiber 1402 blocated in the center of the circle. The center fiber 1402 b will beheld in place or other fused by a media or holding device.

FIG. 14C shows a configuration of a bundle 1403 of nineteen (n=19)fibers, e.g., 1403 a, that have an inner circle 1405 of fibers, and acenter fiber 1403 b.

FIG. 15A shows a bundle 1501 of seven (n=7) fibers, e.g., 1501 a thathas a hexagonal arrangement with a triangular spacing.

FIG. 15B shows a bundle 1502 of nineteen (n=19) fibers, e.g., 1502 athat has a hexagonal arrangement with a triangular spacing.

FIGS. 16A, 16B and 16C shows configurations of bundles of fibers thatare arranged in arbitrary geometric arrangements. These configurationsprovide various levels of density of fibers in the configurations. FIG.16A is an n=16 bundle 1601 of fibers, e.g., 1601 a in a quarter circleconfiguration. FIG. 16B is an n=8 bundle 1602 of fibers, e.g., 1602 b ina square configuration. FIG. 16C is an n=6 bundle 1604 of fibers, e.g.,1604 a in a triangle configuration. FIG. 16D is an n=9 bundle 1603 offibers, e.g., 1603 a in a semicircle configuration.

The following examples are provided to illustrate various embodiments oflaser arrays, systems, apparatus and methods of the present inventions.These examples are for illustrative purposes and should not be viewedas, and do not otherwise limit the scope of the present inventions.

Example 1

An array of blue laser diodes that are spatially combined to make asingle spot in the far-field that can be coupled into a Solarizationresistant optical fiber for delivery to the work piece.

Example 2

An array of blue laser diodes as described in Example 1 that arepolarization beam combined to increase the effective brightness of thelaser beam.

Example 3

An array of blue laser diodes with space between each of the collimatedbeams in the fast axis of the laser diodes that are then combined with aperiodic plate which reflects the first laser diode(s) and transmits asecond laser diode(s) to fill the space between the laser diodes in thefast direction of the first array.

Example 4

A patterned mirror on a glass substrate that is used to accomplish thespace filling of Example 3.

Example 5

A patterned mirror on one side of the glass substrate to accomplish thespace filling of Example 3 and the glass substrate is of sufficientthickness to shift the vertical position of each laser diode to fill theempty space between the individual laser diodes.

Example 6

A stepped heat sink that accomplishes the space filling of Example 3 andis a patterned mirror as described in Example 4.

Example 7

An array of blue laser diodes as described in Example 1 where each ofthe individual lasers are locked by an external cavity to a differentwavelength to substantially increase the brightness of the array to theequivalent brightness of a single laser diode source.

Example 8

An array of blue laser diodes as described in Example 1 where individualarrays of laser diodes are locked to single wavelength using an externalcavity based on a grating and each of the laser diode arrays arecombined into a single beam using either narrowly spaced optical filtersor gratings.

Example 9

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber that has a pure fusedsilica core to create a higher brightness source and a fluorinated outercore to contain the blue pump light.

Example 10

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber that has a GeO₂ dopedcentral core with an outer core to create a higher brightness source andan outer core that is larger than the central core to contain the bluepump light.

Example 11

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber that has a P₂O₅ dopedcore to create a higher brightness source and an outer core that islarger than the central core to contain the blue pump light.

Example 12

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber that has a graded indexcore to create a higher brightness source and an outer core that islarger than the central core to contain the blue pump light.

Example 13

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor fiber that is a graded index GeO₂ doped core andan outer step index core.

Example 14

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor fiber that is a graded index P₂O₅ doped core andan outer step index core.

Example 15

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor fiber that is a graded index GeO₂ doped core.

Example 16

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor fiber that is a graded index P₂O₅ doped core andan outer step index core.

Example 17

Other embodiments and variations of the embodiment of Example one arecontemplated. An array of blue laser diodes as described in Example 1that is used to pump a Raman convertor such as diamond to create ahigher brightness laser source. An array of blue laser diodes asdescribed in Example 1 that is used to pump a Raman convertor such asKGW to create a higher brightness laser source. An array of blue laserdiodes as described in Example 1 that is used to pump a Raman convertorsuch as YVO₄ to create a higher brightness laser source. An array ofblue laser diodes as described in Example 1 that is used to pump a Ramanconvertor such as Ba(NO₃)₂ to create a higher brightness laser source.An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor that is a high pressure gas to create a higherbrightness laser source. An array of blue laser diodes as described inExample 1 that is used to pump a rare-earth doped crystal to create ahigher brightness laser source. An array of blue laser diodes asdescribed in Example 1 that is used to pump a rare-earth doped fiber tocreate a higher brightness laser source. An array of blue laser diodesas described in Example 1 that is used to pump an outer core of abrightness convertor to create a higher ratio of brightness enhancement.

Example 18

An array of Raman converted lasers that are operated at individualwavelengths and combined to create a higher power source whilepreserving the spatial brightness of the original source.

Example 19

An Raman fiber with dual cores and a means to suppress the second orderRaman signal in the high brightness central core using a filter, fiberBragg grating, difference in V number for the first order and secondorder Raman signals or a difference in micro-bend losses.

Example 20

N laser diodes where N≥1 that can be individually turned on and off andcan be imaged onto a bed of powder to melt and fuse the powder into aunique part.

Example 21

N laser diode arrays where N≥1 of Example 1 whose output can be fibercoupled and each fiber can be arranged in a linear or non-linear fashionto create an addressable array of high power laser beams that can beimaged or focused onto a powder to melt or fuse the powder into a uniqueshape layer by layer.

Example 22

One or more of the laser diode arrays combined via the Raman convertorwhose output can be fiber coupled and each fiber can be arranged in alinear or non-linear fashion to create an addressable array of N whereN≥1 high power laser beams that can be imaged or focused onto a powderto melt or fuse the powder into a unique shape layer by layer.

Example 23

An x-y motion system that can transport the N where N≥1 blue lasersource across a powder bed while melting and fusing the powder bed witha powder delivery system positioned behind the laser source to provide afresh powder layer behind the fused layer.

Example 24

A z-motion system that can increment/decrement the height of thepart/powder bed of Example 20 after a new layer of powder is placed.

Example 25

A z-motion system can increment/decrement the height of the part/powderof Example 20 after the powder layer has been fused by the laser source.

Example 26

A bi-directional powder placement capability for Example 20 where thepowder is placed directly behind the laser spot(s) as it travels in thepositive x direction or the negative x direction.

Example 27

A bi-directional powder placement capability for Example 20 where thepowder is placed directly behind the laser spot(s) as it travels in thepositive y direction or the negative y direction.

Example 28

A powder feed system which is coaxial with N laser beams where N≥1.

Example 29

A powder feed system where the powder is gravity fed.

Example 30

A powder feed system where the powder is entrained in an inert gas flow.

Example 31

A powder feed system which is transverse to the N laser beams where N≥1and the powder is placed by gravity just ahead of the laser beams.

Example 32

A powder feed system which is transverse to the N laser beams where N≥1and the powder is entrained in an inert gas flow which intersects thelaser beams.

Example 33

A second harmonic generation system which uses the output of the Ramanconvertor at for example 460 nm to generate light at half the wavelengthof the source laser or 230 nm that consists of an externally resonantdoubling crystal such as KTP but does not allow the short wavelengthlight to propagate through the optical fiber.

Example 34

A third harmonic generation system which uses the output of the Ramanconvertor at for example 460 nm to generate light at 115 nm using anexternally resonant doubling crystal but does not allow the shortwavelength light to propagate through the optical fiber.

Example 35

A fourth harmonic generation system which uses the output of the Ramanconvertor at for example 460 nm to generate light at 57.5 nm using anexternally resonant doubling crystal but does not allow the shortwavelength light to propagate through the optical fiber.

Example 36

A second harmonic generation system which uses the output of arare-earth doped brightness convertor such as Thulium that lases at 473nm when pumped by an array of blue laser diodes at 450 nm to generatelight at half the wavelength of the source laser or 236.5 nm using anexternally resonant doubling crystal but does not allow the shortwavelength light to propagate through the optical fiber.

Example 37

A Third harmonic generation system which uses the output of a rare-earthdoped brightness convertor such as Thulium that lases at 473 nm whenpumped by an array of blue laser diodes at 450 nm to generate light at118.25 nm using an externally resonant doubling crystal but does notallow the short wavelength light to propagate through the optical fiber.

Example 38

A fourth harmonic generation system which uses the output of arare-earth doped brightness convertor such as Thulium that lases at 473nm when pumped by an array of blue laser diodes at 450 nm to generatelight at 59.1 nm using an externally resonant doubling crystal but doesnot allow the short wavelength light to propagate through the opticalfiber.

Example 39

All other rare-earth doped fibers and crystals that can be pumped by ahigh power 450 nm source to generate visible, or near-visible output canbe used in Examples 34-38.

Example 40

Launch of high power visible light into a non-circular outer core orclad to pump the inner core of either the Raman or rare-earth doped corefiber.

Example 41

Use of polarization maintaining fiber to enhance the gain of the Ramanfiber by aligning the polarization of the pump with the polarization ofthe Raman oscillator.

Example 42

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber that is structured tocreate a higher brightness source of a specific polarization.

Example 43

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber that is structured tocreate a higher brightness source of a specific polarization andmaintain the polarization state of the pump source.

Example 44

An array of blue laser diodes as described in Example 1 that is used topump a Raman convertor such as an optical fiber to create a higherbrightness source with a non-circular outer core structured to improveRaman conversion efficiency.

Example 45

The embodiments of Examples 1 to 44 may also include one or more of thefollowing components or assemblies: a device for leveling the powder atthe end of each pass prior to the laser being scanning over the powderbed; a device for scaling the output power of the laser by combiningmultiple low power laser modules via a fiber combiner to create a higherpower output beam; a device for scaling the output power of the bluelaser module by combing multiple low power laser modules via free spaceto create a higher power output beam; a device for combining multiplelaser modules on a single baseplate with imbedded cooling.

It is noted that there is no requirement to provide or address thetheory underlying the novel and groundbreaking performance or otherbeneficial features and properties that are the subject of, orassociated with, embodiments of the present inventions. Nevertheless,various theories are provided in this specification to further advancethe art in this important area, and in particular in the important areaof lasers, laser processing and laser applications. These theories putforth in this specification, and unless expressly stated otherwise, inno way limit, restrict or narrow the scope of protection to be affordedthe claimed inventions. These theories many not be required or practicedto utilize the present inventions. It is further understood that thepresent inventions may lead to new, and heretofore unknown theories toexplain the operation, function and features of embodiments of themethods, articles, materials, devices and system of the presentinventions; and such later developed theories shall not limit the scopeof protection afforded the present inventions.

The various embodiments of lasers, diodes, arrays, modules, assemblies,activities and operations set forth in this specification may be used inthe above identified fields and in various other fields. Additionally,these embodiments, for example, may be used with: existing lasers,additive manufacturing systems, operations and activities as well asother existing equipment; future lasers, additive manufacturing systemsoperations and activities; and such items that may be modified, in-part,based on the teachings of this specification. Further, the variousembodiments set forth in this specification may be used with each otherin different and various combinations. Thus, for example, theconfigurations provided in the various embodiments of this specificationmay be used with each other; and the scope of protection afforded thepresent inventions should not be limited to a particular embodiment,configuration or arrangement that is set forth in a particularembodiment, example, or in an embodiment in a particular Figure.

The invention may be embodied in other forms than those specificallydisclosed herein without departing from its spirit or essentialcharacteristics. The described embodiments are to be considered in allrespects only as illustrative and not restrictive.

1-48. (canceled)
 49. An addressable array laser processing system, theaddressable array laser processing system comprising: at least threelaser systems of claim 67; each of the at least three laser systemsconfigured to couple each of their combined laser beams into a singleoptical fiber; whereby each of the at least the three combined laserbeams being capable of being transmitted along its coupled opticalfiber; the at least three optical fibers in optical association with alaser head; and a control system; wherein the control system comprises aprogram having a predetermined sequence for delivering each of thecombined laser beams at a predetermined position on a target material.50. The addressable array of claim 49, wherein the predeterminedsequence for delivering comprises individually turning on and off thelaser beams from the laser head, thereby imaging onto a bed of powder tomelt and fuse the target material comprising a powder into a part. 51.The addressable array of claim 49, wherein the fibers in the laser headare configured in an arrangement selected from the group consisting oflinear, non-linear, circular, rhomboid, square, triangular, andhexagonal.
 52. The addressable array of claim 49, wherein the fibers inthe laser head are configured in an arrangement selected from the groupconsisting of 2×5, 5×2, 4×5, at least 5× at least 5, 10×5, 5×10 and 3×4.53. The addressable array of claim 49, wherein the target materialcomprises a powder bed; and, comprising: an x-y motion system, capableof transporting the laser head across a powder bed, thereby melting andfusing the powder bed; and a powder delivery system positioned behindthe laser source to provide a fresh powder layer behind the fused layer.54. The addressable array of claim 53, comprising: a z-motion system,capable of transporting the laser head to increment and decrement aheight of the laser head above a surface of the powder bed.
 55. Theaddressable array of claim 53, comprising: a bi-directional powderplacement device capable of placing powder directly behind the deliveredlaser beam as it travels in the positive x direction or the negative xdirection.
 56. The addressable array of claim 53, comprising a powderfeed system that is coaxial with a plurality of laser beam paths. 57.The addressable array of claim 53, comprising a gravity feed powdersystem.
 58. The addressable array of claim 53, comprising a powder feedsystem, wherein the powder is entrained in an inert gas flow.
 59. Theaddressable array of claim 53, comprising a powder feed system that istransverse to N laser beams where N≥1 and the powder is placed bygravity ahead of the laser beams.
 60. The addressable array of claim 53,comprising a powder feed system that is transverse to N laser beamswhere N≥1 and the powder is entrained in an inert gas flow whichintersects the laser beams.
 61. (canceled)
 62. (canceled)